1. Field of the Invention
This invention relates to submersible pumps for moving liquids such as waste liquids and sewage which pumps are housed in a pit and submerged in the liquid. In particular, the invention relates to a means of quickly and easily disengaging the working parts of the pump from its associated discharge piping for servicing and cleaning of the pump.
2. Prior Art
Submersible pumps have been in use for a long time to remove waste liquids by draining the liquid into a pit or enclosure in which the pump is located, and discharging the waste liquid through a discharge pipe or conduit connected to the output of the pump. Heretofore, when the pump required servicing, e.g., cleaning because a foreign object had lodged in the pump or discharge opening and prevented normal operation, it had to be lifted from the pit. Therefore, someone had to disconnect the pump from the discharge pipe by entering the pit and removing bolts or other connections to allow the pump to be lifted out.
Needless to say, it is a disagreeable task for someone to climb down into a pit of waste liquids and disassemble the pump to permit its removal. To avoid this problem, it has been proposed, as described in U.S. Pat. No. 3,592,564 to provide the pump discharge opening with a flexible seal which is forced into sealing engagement with the adjacent flange of the discharge pipe when the pump is in service. This required precise alignment of the pump discharge opening and the adjacent flange of the discharge pipe when the pump was lowered into the pit.
This problem was solved, as described in the patent, by providing a vertical guide rail which allowed the entire pump to be lifted out for servicing and placed back into position. As will be appreciated by those skilled in this art, such installations are more expensive because they require the installation of a guide rail and a larger size diameter pit in order to accommodate the guide rail. These installations also require great care when lifting the pump out and repositioning it, because of the accuracy of alignment required, as discussed above.